CaltechAUTHORS
Published April 1, 2012 | Version Published
Journal Article Open

The S^4G Perspective on Circumstellar Dust Extinction of Asymptotic Giant Branch Stars in M100

Creators

  • 1. ROR icon Max Planck Society
  • 2. ROR icon National Radio Astronomy Observatory
  • 3. ROR icon European Space Research and Technology Centre
  • 4. ROR icon Carnegie Observatories
  • 5. ROR icon Instituto de Astrofísica de Canarias
  • 6. ROR icon University of La Laguna
  • 7. ROR icon Laboratoire d'Astrophysique de Marseille
  • 8. ROR icon University of Arizona
  • 9. ROR icon California Institute of Technology
  • 10. ROR icon Space Telescope Science Institute
  • 11. ROR icon Complutense University of Madrid
  • 12. ROR icon European Southern Observatory
  • 13. ROR icon University of Oulu
  • 14. ROR icon University of Turku
  • 15. ROR icon Korea Astronomy and Space Science Institute

Abstract

We examine the effect of circumstellar dust extinction on the near-IR (NIR) contribution of asymptotic giant branch (AGB) stars in intermediate-age clusters throughout the disk of M100. For our sample of 17 AGB-dominated clusters we extract optical-to-mid-IR spectral energy distributions (SEDs) and find that NIR brightness is coupled to the mid-IR dust emission in such a way that a significant reduction of AGB light, of up to 1 mag in the K band, follows from extinction by the dust shell formed during this stage. Since the dust optical depth varies with AGB chemistry (C-rich or O-rich), our results suggest that the contribution of AGB stars to the flux from their host clusters will be closely linked to the metallicity and the progenitor mass of the AGB star, to which dust chemistry and mass-loss rate are sensitive. Our sample of clusters—each the analogue of a ~1 Gyr old post-starburst galaxy—has implications within the context of mass and age estimation via SED modeling at high-z: we find that the average ~0.5 mag extinction estimated here may be sufficient to reduce the AGB contribution in the (rest-frame) K band from ~70%, as predicted in the latest generation of synthesis models, to ~35%. Our technique for selecting AGB-dominated clusters in nearby galaxies promises to be effective for discriminating the uncertainties associated with AGB stars in intermediate-age populations that plague age and mass estimation in high-z galaxies.

Additional Information

© 2012 The American Astronomical Society. Received 2011 December 18; accepted 2012 February 29; published 2012 March 19. S.E.M. thanks Arjen van der Wel for discussion and Angela Adamo and Anibal Garcia for their helpful comments on the manuscript. E.A. and A.B. thank the Centre National d'Etudes Spatiales for financial support.

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Additional details

Identifiers

Eprint ID
31252
Resolver ID
CaltechAUTHORS:20120501-131704328

Funding

Centre National d'Études Spatiales (CNES)

Dates

Created
2012-05-01
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Updated
2021-11-09
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Caltech Custom Metadata

Caltech groups
Infrared Processing and Analysis Center (IPAC)